Can punch



May 21, 1935.

B. E. DOUGHERTY CAN PUNCH Filed Feb. 6, 1934 Patented May 21, 1935 I UNITED STATES PATENT OFFICE CAN PUNCH Bernard E. Dougherty, Seattle, Wash.

Application February 6, 1934, Serial No. 710,037

11 Claims. (Cl- 164-120) This invention relates to a can punch and more In the accompanying drawing illustrating cerparticularly to a manually operable can punch tain preferred embodiments of my invention: adapted for use on flanged cans, and more espe- Figure 1 illustrates a can punch embodying my cially soldered cans wherein the flange is little invention, as applied to a can being punctured;

or no more than the thickness of the metal. Figure 2 illustrates another form of can punch 5 From time to time there have appeared can showing my invention applied to a can being punches involving clamps which embrace the can perforated; and to be punctured. Such devices are cumbersome Figure 3 illustrates another form of can punch and are not conveniently adapted for use on similar in some respects to that illustrated in various size cans. 'It is desirable that can punches Figure 1. Y 10 make an opening adjacent the edge of the can Referring to Figure 1, there is shown a can whereby the whole of the contents may conpunch comprising a puncture point 2 on a memveniently be poured from the can. The types her 3 pivoted on a fulcrum 4 and rotatable about of punches depending upon embracing the can such fulcrum by a handle 5. The fulcrum is part with a clamp are not only difilcult of manipulaof a bracket 6 having a tooth I for engagement 15 tion and bulky to store, but are almost without with the flange 8 of the can 8, and a foot It for exception limited to spaced perforations which, engagement with the top I I of the can. The on larger sized cans, lie inwardly of the edge and punch is shown in dotted lines in initial position render diificult the emptying of the can inasmuch prior to perforation of the can and in solid lines as inverting the can to present the opening to in position shortly before completion of the punc- 20 the last of the contained liquid results in air turing operation. locking. My improved can punch is operable The bracket 6 comprises a generally flat porwith equal facility and eificiency upon cans of tion I! having an opening I; therein through any size, always making the perforation adjacent which she member 3 is free to operate. The ful-' the edge of the can of any size; the perforation crum 4, in the embodiment shown in Figure 1, 25 can be made adjacent the edge of the can iris formed by cars l4 upstanding on each side of respective of its size, resultinginutmost efllciency the flat portion l2, having holes therein into in providing an air relief hole and an emptying which outstanding lugs I5 on the member 3 exhole'diametrically opposed and adjacent the edge tend to form a balanced pivot. It will be noted of any size can. that the edge :6 of the hole [3 is so positioned 80 Other can punches have been devised which that rotational movement of the member 3 about combine handles for manipulating the can after the fulcrum 4 is limited, whereby puncturing perforation. It is not my purpose to provide of the side of the can by the point 2 is obviated.

a. handle to serve to hold a can. My improved In the embodiment shown in Figure 1, the fill-7 can punch is operable manually and convenientcrum 4 lies outwardly (radially of the can) from 85 ly with the same general motions as employed the point of engagement of the tooth I. In this with a cap remover for crown seals. It is readily arrangement, the reaction of the lugs ii at the applied to a can, taking a firm and tenacious grip fulcrum 4 tends to pivot the bracket about the thereon irrespective of the size of the flange on P t O engagement of the tooth with a 8 40 the can and readily perforating the same and 8 thus initially pressing the foot I into engage- 4o shearing the metal if desired back to the edge of ment with the top of the can. An equilibrium of the can forming a clean opening without inforces having been thus established, the fulcrum terior obstruction at the most efllcient point of 4 b mes fix d w r p t the can a d 1111'- the can for emptying the same. My can punch ther effort applied to the handle 5 to rotate the is particularly well suited for'condensed milk cans poi t 2 a ut the fulcrum 4 causes perforation as which, by common acceptance, are soldered cans of the as foot assists tooth T in taking the having a flange no thicker than the material of reaction, and a shearing action toward the wall the can.. Can punches as ordinarily available fail of the can. The sides of the member 3 from the to engage such a small flange with sufflcient poin 2 fl y constitute Shearing 511118068,

tenacity to resist the reaction forces developed in and the fixing of the pivot point as aforesaid by puncturing the can. My can punch is so com the establishment of an equilibrium of forces, restituted that no manipulation other than the suits, upon rotation of the member 3 into the can, familiar operation of a bottle cap remover is in a cutting action on each side of the member required in perforating a can even with so slight 3. Due to the shape of the member 3, the cut a flange. material is rolled. It will be noted that the cut- 66 punch comprising a point 2' formed at the end of a. member 3, the extension of which forms a handle The member 3' has an opening therein through which extends a bracket 3 which is provided with a tooth I for engagement with the flange 8' of a. can 8', and a foot Ill. The bracket 6 has-a fulcrum 4' for engagement with the member 3'. The initial position of the can punch prior to perforation of the can is shown in dotted lines. The position of the can punch just prior to its maximum movement is shown in solid lines. A shoulder it limits the rotational movement of the member 3' about the fulcrum 4' whereby puncturing of the side of the can is obviated.

In the embodiment shown in Figure 2, the foot It does not initially engage the top of the can to be punctured. The tooth I is engaged with the flange 8 of the can 9 and the point 2' is engaged with the surface to be punctured. Upward movement of the handle 5' first pivots the bracket 6' about the tooth 1' until the fulcrum 4' has reached a point where the line between the fulcrum 4 and tooth 1' is generally normal to the line-joining the fulcrum 4' and the point 2. The bracket 6' may move slightly in the slot in the member 3' until the fulcrum 4 has found the tion is established, the point 2' may or may have not punctured the can, depending upon how far the top of the can is elevated above the point of engagement of the tooth I and the flange 8'. When the foot I 0' has engaged the surface to be punctured, however, the fulcrum 4' becomes fixed with respect to the can and the member 3' rotates about it, whereby the sides of the member 3' forcibly shear the punctured can toward the wall of the container. The sides of the member 3' are shear surfaces adapted for cutting the metal, being preferably squarely formed and smooth. The shape of the member 3' is such that the sheared metal is not rolled but is forced backwardly as a flap to lie flat against the side ofthe can when the shoulder it has been engaged and the movement has reached its limit. A tongue I! is struck outwardly from the bracket to avoid the bracket slipping out of the hole in the member 3' when the implement is removed from the can.

In Figures there is shown a simpler form of can punch generally similar to the form shown in Figure 1. 'In this embodiment a point 2" and a member 3" are mounted for rotation about a fulcrum 4" by means of a handle 5". The fulcrum 4" is supported by a bracket 6" having a tooth 1" and a foot Hi". In this particular embodiment the bracket is a flat stamping riveted to the member 3", the rivet constituting a pivot point at the fulcrum 4". The member 3" and handle 5" are portions of the same stamping, the end of the member 3 being turned to approximately ninety degrees from the plane of that portion which lies adjacent the bracket, thereby forming a shear member and puncture point. The shear member is preferably generally triangular in shape expanding in section rearwardly of the point 2", whereby the hole sheared in the can has its greatest width nearest the edge of the can. In this respect, the punch shown in Figure 3 is th; same as the punches shown in Figures 1 and The side of the member I" as indicated at It serves to limit the rotation of the member 3" about the fulcrum 4" by engaging the bracket 8".

It will be observed that my improved punch is not limited in any respect by the diameter of the can being operated upon, and that no clamps are required to hold the can, the implement being operable with one hand by a simple upward movement. The arrangement of the parts as illustrated and described results in a very powerful gripping action on the can, and even prior to the time the puncture point 2 has actually perforated at the top of the can, it is practically impossible to pull the device away from the can as long as upward pressure is applied in suflicient amount to keep the tooth of the bracket engaged with the flange of the can. It is this powerful gripping action developed by the implement which renders it suitable for cans having flanges virtuafly no thicker than the material of the can. This condition exists in practically all soldered cans, which have no rolled bead at the edges. The implement, of course, operates with equal facility on cans having rubber sealed rolled edges, or any other form of offset adjacent the top edge, and by the term flange as used in the claims with reference to cans, I mean to include offset portions serving the function of the flange in the illustrated application of my can punch.

My improved can punch is economical to manufacture, the parts beingeasiiy formed by stamping. The embodiment shown in Figure 2 for example requires merely two stampings simple in contour and easily formed with a single operation. The assembly of this embodiment involves nothing more than slipping the bracket 6' in the hole in the member 3' and bending the tongue I! sideways slightly to obviate the bracket slipping out of the hole. The embodiment shown in Figure 3 is slightly more difficult to form and in its assembly involves riveting, nevertheless it is not expensive to manufacture. The embodiment shown in Figure 1 involves a somewhat more complicated stamping. It is, however, no more involved than the forms commonly found in less eflicient devices, it being borne in mind that my improved can punch is a complete'unlt in itself requiring no extraneous bands or clamps, and that it will function efllciently upon cans of any size and flanges of practically any thickness, always placing the opening in the most efficient place for emptying the can.

The associated elements of my improved can punch are so disposed that the reactions developed by thrusting the puncture point into the can and shearing the metal away from the punctured hole are most efiflciently utilized for developing a gripping action to hold the implement to the can during the puncturing operation. In the embodiment shown in Figure l, the foot of the bracket initially engages the surface to be punctured, causing the fulcrum point to be fixed relative to the can even prior to the breaking through of the puncture point. Thus, the shearing motion is developed and made available immediately that the can has been pierced. In the embodiment shown in Figure 2, the pressure foot ordinarily engages the surface to be punctured after the puncture point has pierced the can so that the shearing action may or may not exist immediately after the can is pierced depending upon whether the foot has or has not contacted with the surface being punctured. The pivot point in all cases is preferably so disposed with respect to the tooth, and the puncture point and shearing surfaces adjacent it are so shaped, that as the puncturing member fulcrums on the pivot point increasingly wider portions of the puncturing member engage the surface being punctured whereby the opening formed is of greatest dimension adjacent the rim of the can. For thin liquids this is not essential, but for more viscous fluids such as condensed milk it is desirable.

To my knowledge, my improved can punch is the first to utilize the reaction forces developed by the mere raising of a handle to cause the punch to grip the upper flange of the can, thus freeing the operator from the annoyance of learning unfamiliar motions to operate the punch and also making the punch equally eflicient for cans of any height, diameter or character of flange.

While I have illustrated and described certain preferred embodiments of my invention, it will be understood that the invention is not so limited but may be otherwise embodied within the scope of the following claims.

I claim:

1. A can punch comprising a rotatable member having a puncture point at the end thereof, and a bracket having a fulcrum thereon for the rotatable member, the bracket having a tooth for engaging the flange of a can to be punctured, the puncture point lying in advance of the tooth and fulcrum and the distance from the fulcrum to the tooth being great enough that the fulcrum will lie above the top of the flange of a can to be punctured when the tooth has engaged the flange, and the bracket being freely pivoted at the fulcrum so that the parts will assume such position upon application to a can, and thus the reaction of the member on the fulcrum acts to draw the tooth into engagement with the flange of a can being punctured.

2. A can punch comprising a rotatable member having a shear surface thereon terminating in a puncture point at the end thereof, and a bracket having a fulcrum thereon for the rotatable member, thebracket having a tooth for engaging the flange of a can to be punctured, the puncture point lying in advance of the tooth and fulcrum and the distance from the fulcrum to the tooth being great enough that the fulcrum will lie above the top of the flange of a can to be punctured when the tooth has engaged the flange, and the bracket being freely pivoted at the fulcrum so that the parts will assume such position upon application to a can, and thus the reaction of the member on the fulcrum acts to draw the tooth into engagement with the flange of a can being punctured.

3. A, can punch comprising a rotatable member having a puncture point at the end thereof, and a bracket having a fulcrum thereon for the rotatable member, there being a handle on the rotatable member disposed on the side of the fulcrum opposite the puncture point, the bracket having a fulcrum thereon for the rotatable member, the bracket having a tooth for engaging the flange of a can to be punctured, the puncture point lying in advance of the tooth and fulcrum and the distance from the fulcrum to the tooth being great enough that the fulcrum will lie above the top of the flange of a can to be punctured when the tooth has engaged the flange, and the bracket being freely pivoted at the fulcrum so that the parts will ass e such position upon application to a can, and thus the reaction of the member on the fulcrum upon rotational motion being imparted to the handle acts to draw the tooth into engagement with the flange of a can being punctured.

4. A can punch comprising a rotatable member having a shear surface thereon terminating in a puncture point at the end thereof, and a bracket for temporarily providing a fulcrum for the rotatable member while puncturing a can, said bracket having a fulcrum for said rotatable member, a tooth for engaging the flange of a can to be perforated, and a foot for engaging the surface to be perforated, the foot lying in advance of the puncture point, and the tooth lying behind the puncture point whereby a reaction from the puncture point tending to draw the tooth into engagement with the flange of a can to be punctured operates to press the foot into engagement with the surface being punctured and thereby fixes the pivot point with respect to the can, thus enabling the shear surface to sweep toward the tooth and shear the can from the point of initial puncture toward the flange.

5. A can punch according to claim 4 having means on the bracket limiting the rotation of the rotatable member about the fulcrum.

6. A punch for flanged cans comprising a rotatable member and a bracket, said bracket including a pressure foot and a flange engaging tooth, said rotatable member including a piercing point at one end thereof extending into shearing surfaces, said rotatable member being fulcrumed on said bracket, the fulcrum point being fixed when said foot and said tooth are in engagement with a can, whereby shearing is effected upon rotation of the rotatable member.

7. A can punch comprising a member having a shearing surface terminating in a puncture point at the end of the member, and a bracket adapted to engage a can during a puncturing operation and provide a temporary fulcrum for said member adjacent the end of the can, said bracket having a fulcrum for the member, a foot engageable with the surface to be punctured and a tooth engageable with the flange of a can being punctured, the arrangement being such that the reaction on the fulcrum by the member during rotation thereof draws the tooth into engagement with the flange of the can being punctured and tends to rotate the bracket about the tooth to press the foot into contact with the surface of the can, thus holding the bracket to the can solely by the reaction of the puncturing operation and fixing the fulcrum with respect to the can whereby shearing of the can toward the tooth is effected upon rotation of the member.

8. A can punch comprising a generally flat stamping having a puncture point at one end thereof and a portion serving as a handle at the other end thereof, and a bracket retained in a hole in said stamping disposed adjacent the puncture point, the bracket being retained by a protuberance engageable with the upper side of the stamping to form a fulcrum therefor, and by a distortion of the surface of the bracket below the stamping, said bracket terminating at one end in a tooth engageable with the flange of a can to be punctured, and having a foot at the other end thereof engageable with-the can surface to be punctured.

Q. A can punch comprising a generally flat stamping having a puncture point at one end thereof and a portion serving as a handle at the other end thereof, and a bracket retained in a hole tured, and having a foot at the other end thereof engageable with the can surface to be punctured, and means on the bracket limiting the rotation of the member upon the fulcrum.

10. A can punch comprising a rotatable member having a puncture point at the end thereof,

and a bracket for engagement with a can to be punctured, a fulcrum on said bracket about which said member is rotatable, a tooth at one end of said bracket and a foot at the other end thereof, the foot and tooth being so disposed with respect to the fulcrum that the reaction of the member on the fulcrum tends to rotate the bracket about the tooth in the same direction of rotation as the rotation of the rotatable member inducing the reaction.

11. A can punch comprising a rotatable member having a generally claw-shaped puncture point with shear surfaces on the sides thereof, and a bracket pivoted to said member, a tooth on the bracket disposed a smaller distance from the pivot than from the puncture point and lying in a plane generally normal to the plane through the pivot including the puncture point upon initial application of the can punch to a can to be punctured, whereby the forces induced by rotation of the puncture point forces the tooth into engagement with a flange on the can, the claw-shaped puncture point tending to draw the tooth radially into closer engagement with the can during continued enlargement of a perforation.

BERNARD E. DOUGHERTY. 20 

